package com.api.test;

import java.text.Collator;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.os.Bundle;
import android.view.View;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.app.ListActivity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;

public class MainActivity extends ListActivity {
	
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        
        Intent intent = getIntent();
        String path = intent.getStringExtra("com.example.android.apis.Path");
        
        if (path == null) {
			path = "";
		}
        
        setListAdapter(new SimpleAdapter(this, getData(path), 
        		android.R.layout.simple_list_item_1, new String[]{"title"}, 
        		new int[]{android.R.id.text1}));
        getListView().setTextFilterEnabled(true);
    }
    
    protected List getData(String prefix) {
		List<Map> myData = new ArrayList<Map>();
		
		Intent mainIntent = new Intent(Intent.ACTION_MAIN, null);
		mainIntent.addCategory(Intent.CATEGORY_SAMPLE_CODE);
		
		PackageManager pm = getPackageManager();
		List<ResolveInfo> list = pm.queryIntentActivities(mainIntent, 0);
		
		if (null == list) {
			return myData;
		}
		
		String[] prefixPath;
		
		if (prefix.equals("")) {
			prefixPath = null;
		} else {
			prefixPath = prefix.split("/");
		}
		
		int len = list.size();
		
		Map<String, Boolean> entries = new HashMap<String, Boolean>();
		
		for (int i = 0; i < len; i++) {
			ResolveInfo info = list.get(i);
			CharSequence  labelSeq = info.loadLabel(pm);
			String label = labelSeq != null ? labelSeq.toString() : info.activityInfo.name;
			
			if (prefix.length() == 0 || label.startsWith(prefix)) {
				String[] labelPath = label.split("/");
				String nextLabel = prefixPath == null ? labelPath[0] : labelPath[prefixPath.length];
				
				if ((prefixPath != null ? prefixPath.length : 0) == labelPath.length - 1) {
					addItem(myData, nextLabel, activityIntent(info.activityInfo.applicationInfo.packageName, info.activityInfo.name));
				} else {
					if (entries.get(nextLabel) == null) {
						addItem(myData, nextLabel, browseIntent(prefix.equals("") ? nextLabel : prefix + "/" + nextLabel));
						entries.put(nextLabel, true);
					}
				}
			}
		}		
		Collections.sort(myData, sDisplayNameComparator);
		return myData;
	}
    
    private final static Comparator<Map> sDisplayNameComparator = new Comparator<Map>() {
    	private final Collator collator = Collator.getInstance();

		@Override
		public int compare(Map map1, Map map2) {
			return collator.compare(map1.get("title"), map2.get("title"));
		}
	};
	
	protected Intent activityIntent(String pkg, String componentName) {
		Intent result = new Intent();
		result.setClassName(pkg, componentName);
		return result;
	}
	
	protected Intent browseIntent(String path) {
		Intent result = new Intent();
		result.setClass(this, MainActivity.class);
		result.putExtra("com.example.android.apis.Path", path);
		return result;
	}
	
	protected void addItem(List<Map> data, String name, Intent intent) {
		Map<String, Object> temp = new HashMap<String, Object>();
		temp.put("title", name);
		temp.put("intent", intent);
		data.add(temp);
	}

	@Override
	protected void onListItemClick(ListView l, View v, int position, long id) {
		Map map = (Map) l.getItemAtPosition(position);
		
		Intent intent = (Intent) map.get("intent");
		startActivity(intent);
	}
    
}
